Masonry cement composition, masonry construction and method

Abstract

A masonry cement is prepared by dry mixing portland cement, diatomaceous earth and a water-swellable colloidal clay, such as bentonite. Accordingly, the crushed limestone and other ingredients previously included in masonry cements for admixture with portland cement can be completely eliminated and substituted by diatomacious earth and water-swellable colloidal clay. In this manner, a combination of less than about 10% by weight of a combination of diatomaceous earth and colloidal clay replaces approximately 50% by weight crushed limestone and other ingredients from prior art masonry cement compositions while providing a masonry cement which meets ASTM specifications, particularly for air entrainment, water retention and compressive strength.

We claim: 
     
       1. A masonry cement composition comprising Portland cement, about 0.05% to about 0.8% by weight diatomaceous earth and about 5% to about 16% by weight colloidal clay. 
     
     
       2. The masonry cement of claim 1 wherein said Portland cement is in an amount of at least 75% by weight of the entire composition. 
     
     
       3. The masonry cement of claim 2 wherein said Portland cement is included in an amount of about 83.2% to about 95% by weight. 
     
     
       4. The masonry cement of claim 1 wherein said colloidal clay comprises bentonite. 
     
     
       5. The masonry cement of claim 4 wherein said diatomaceous earth has a surface area of at least 20 square meters per gram. 
     
     
       6. A masonry cement composition consisting essentially of 75-95% by weight Portland cement; 0.05-0.8% by weight diatomaceous earth and 5-16% by weight water swellable colloidal clay. 
     
     
       7. The masonry cement of claim 6 wherein said colloidal clay comprises bentonite. 
     
     
       8. A method of masonry construction comprising mixing sand and water into a dry masonry cement composition to form a mortar, and applying a layer of said mortar onto a surface of a first masonry building member and disposing a secondary masonry building member in contact with said mortar layer to sandwich said mortar layer between said first and second building members thereby to structurally secure said first and second building members together, said masonry cement composition comprising Portland cement, about 0.05% to about 0.8% by weight diatomaceous earth and about 5% to about 16% by weight water swellable colloidal clay. 
     
     
       9. A method as defined in claim 8 wherein said masonry cement includes Portland cement in an amount of at least 75% of said masonry cement. 
     
     
       10. A method as defined in claim 9 wherein said Portland cement comprises about 83.2% to about 95% by weight of said masonry cement. 
     
     
       11. A method as defined in claim 8 wherein said masonry cement composition consists essentially of 75%-95% by weight Portland cement; 0.05%-0.8% by weight diatomaceous earth and 5%-16% by weight colloidal clay, said percentages based upon the total weight of the masonry cement composition. 
     
     
       12. The method as defined in claim 8 wherein said colloidal clay comprises bentonite. 
     
     
       13. The method as defined in claim 12 wherein said diatomaceous earth has a surface area of at least 20 square meters per gram. 
     
     
       14. The method as defined in claim 13 wherein said diatomaceous earth has a surface area of at least 60 square meters per gram. 
     
     
       15. A method of manufacturing a masonry cement composition comprising dry blending a composition comprising Portland cement, 0.05% to 0.8% by weight diatomaceous earth and 5% to 16% water swellable colloidal clay. 
     
     
       16. The method as defined in claim 15 wherein said colloidal clay comprises bentonite and wherein said diatomaceous earth has a surface area of at least 20 square meters per gram. 
     
     
       17. The method as defined in claim 15 wherein said Portland cement is included in an amount of at least 75% of said masonry cement. 
     
     
       18. The method as defined in claim 17 wherein said Portland cement is included in an amount of about 83.2% to about 95% by weight of said masonry cement.